"""Plot exp (a): TTFT vs prefix length for miss / gpu-hit / cpu-hit (+ PCIe floor)."""
import json
import sys
from pathlib import Path

import matplotlib
matplotlib.use("Agg")
import matplotlib.pyplot as plt

R = Path(sys.argv[1] if len(sys.argv) > 1 else "v2/exp_a_tier_latency/results")
FIG = Path(sys.argv[2] if len(sys.argv) > 2 else "v2/figs/exp_a_tier_latency.png")
KV_BYTES_PER_TOKEN = 98304


def load(name):
    p = R / name
    return json.load(open(p)) if p.exists() else None


miss, gpu, cpu, pcie = load("miss.json"), load("gpu.json"), load("cpu.json"), load("pcie.json")


def series(d):
    if not d:
        return [], []
    items = sorted(((int(k), v["ttft_p50"]) for k, v in d["by_length"].items()), key=lambda x: x[0])
    return [a for a, _ in items], [b for _, b in items]


fig, ax = plt.subplots(figsize=(7.2, 5.0))
for d, lab, mk, c in [(miss, "miss (recompute)", "o", "#d62728"),
                      (cpu, "CPU-tier hit (DRAM offload)", "s", "#ff7f0e"),
                      (gpu, "GPU-tier hit (HBM APC)", "^", "#2ca02c")]:
    xs, ys = series(d)
    if xs:
        ax.plot(xs, ys, marker=mk, label=lab, color=c, linewidth=2, markersize=7)

if pcie:
    items = sorted(((int(k), v["transfer_s"]) for k, v in pcie["by_length"].items()))
    xs = [a for a, _ in items]; ys = [b for _, b in items]
    ax.plot(xs, ys, "--", color="#7f7f7f", linewidth=1.4,
            label="CPU-hit transfer floor (PCIe H2D)")

ax.set_xscale("log", base=2); ax.set_yscale("log")
ax.set_xlabel("Reused prefix length (tokens)")
ax.set_ylabel("TTFT (s, log)")
ax.set_title("Cost of serving a reused prefix from each KV tier\nQwen3-Coder-30B-A3B, 1xH20")
ax.grid(True, which="both", alpha=0.3)
ax.legend()
FIG.parent.mkdir(parents=True, exist_ok=True)
fig.tight_layout(); fig.savefig(FIG, dpi=140)
print("wrote", FIG)

# Table
print(f"\n{'L':>7} {'miss(s)':>10} {'cpu(s)':>10} {'gpu(s)':>10} {'miss/cpu':>9} {'cpu/gpu':>9}")
allL = sorted({int(k) for d in (miss, gpu, cpu) if d for k in d["by_length"]})
for L in allL:
    m = miss["by_length"].get(str(L), {}).get("ttft_p50") if miss else None
    c = cpu["by_length"].get(str(L), {}).get("ttft_p50") if cpu else None
    g = gpu["by_length"].get(str(L), {}).get("ttft_p50") if gpu else None
    f = lambda x: f"{x:.4f}" if x is not None else "   -  "
    r1 = f"{m/c:.1f}x" if (m and c) else "  -"
    r2 = f"{c/g:.1f}x" if (c and g) else "  -"
    print(f"{L:>7} {f(m):>10} {f(c):>10} {f(g):>10} {r1:>9} {r2:>9}")

if cpu:
    vf = {k: v.get("verified_frac") for k, v in cpu["by_length"].items()}
    print("\nCPU-tier verified fraction (ext_hits>0):", vf)